بسم الله الر حمن الر حيم
Tobacco, plant grown commercially for its leaves and
stems, which are rolled into cigars, shredded for use in cigarettes and pipes,
processed for chewing, or ground into snuff, a fine powder that is inhaled
through the nose. Tobacco is the source of nicotine, an addictive
drug that is also the basis for many insecticides (see
Smoking).
Tobacco is a member of the
nightshade family. There are more than 70 species of tobacco, of
which 45 are native to the Americas. The two cultivated species, common tobacco
and wild tobacco, are annuals—they live only one growing season. Common tobacco
is 1 to 3 m (3 to 10 ft) tall and has a thick, woody stem with few side
branches. One plant typically produces 10 to 20 broad leaves that branch
alternately from the central stalk. The leaf size depends on the strain. The
narrow, trumpet-shaped flowers are dark pink to almost white. Wild tobacco is
about 0.6 m (2 ft) tall and has a stem that is more slender and less woody than
common tobacco. The leaves have a short stalk that attaches to the stem. The
flowers are pale yellow with five separate lobes.
